Automatic door and window closers and similar retraction devices for tools and the like are well known in the art. Typically, they comprise a spring or gravity power device to close the window or door once it is pulled open.
However, there are significant disadvantages to the prior art retraction devices and thus there is a continuing need for improvement in this field. Many of these prior art devices are extremely complex, large, unsightly and expensive to manufacture. In addition, the devices which use springs to accomplish the automatic closing typically fail to provide an effective braking feature to prevent slamming of the door or window as it closes. Moreover, many of these prior devices fail to provide an adjustable braking force to take into account doors and windows of differing sizes and frictional conditions. In the devices using pistons with adjustable orifices to control braking, the overall structure of the apparatus tends to be rather large and unsightly.
Examples of these prior art devices are disclosed in the following U.S. Pat. Nos.: 916,455 to Kush et al; 2,635,282 to Trammell, Sr. et al; 2,658,231 to Guttormsen; 2,895,779 to Bender; 2,992,450 to Pittenger; 3,020,580 to Glenn; 3,045,276 to Schwarz; 3,103,034 to Fisher; 3,143,773 to Glenn; 3,246,363 to Rogas et al; 3,267,513 to Wartian; 3,278,979 to Clement; 3,332,638 to Jessup et al; 3,334,444 to Hargrove; 3,389,422 to Glenn; 3,480,227 to Matthews; 3,502,280 to Jessup et al; 3,699,608 to Schwarz; 3,756,585 to Mihalcheon; 4,003,102 to Hawks et al; 4,004,372 to Beard et al; 4,126,912 to Johnson; 4,301,623 to Demukai; and 4,330,960 to Hasemann et al.